Yoshida Hideji, Wada Akira, Shimada Tomohiro, Maki Yasushi, Ishihama Akira
Department of Physics, Osaka Medical College, Takatsuki, Japan.
Yoshida Biological Laboratory, Kyoto, Japan.
Front Genet. 2019 Dec 4;10:1153. doi: 10.3389/fgene.2019.01153. eCollection 2019.
Transcription and translation in growing phase of , the best-studied model prokaryote, are coupled and regulated in coordinate fashion. Accordingly, the growth rate-dependent control of the synthesis of RNA polymerase (RNAP) core enzyme (the core component of transcription apparatus) and ribosomes (the core component of translation machinery) is tightly coordinated to keep the relative level of transcription apparatus and translation machinery constant for effective and efficient utilization of resources and energy. Upon entry into the stationary phase, transcription apparatus is modulated by replacing RNAP core-associated sigma (promoter recognition subunit) from growth-related RpoD to stationary-phase-specific RpoS. The anti-sigma factor Rsd participates for the efficient replacement of sigma, and the unused RpoD is stored silent as Rsd-RpoD complex. On the other hand, functional 70S ribosome is transformed into inactive 100S dimer by two regulators, ribosome modulation factor (RMF) and hibernation promoting factor (HPF). In this review article, we overview how we found these factors and what we know about the molecular mechanisms for silencing transcription apparatus and translation machinery by these factors. In addition, we provide our recent findings of promoter-specific transcription factor (PS-TF) screening of the transcription factors involved in regulation of the and genes. Results altogether indicate the coordinated regulation of Rsd and RMF for simultaneous hibernation of transcription apparatus and translation machinery.
在研究最为透彻的原核生物模式中,转录和翻译在生长阶段是偶联的,并以协调的方式进行调控。因此,依赖生长速率对RNA聚合酶(RNAP)核心酶(转录装置的核心组分)和核糖体(翻译机器的核心组分)合成的控制紧密协调,以保持转录装置和翻译机器的相对水平恒定,从而有效且高效地利用资源和能量。进入稳定期后,通过将与RNAP核心相关的σ因子(启动子识别亚基)从与生长相关的RpoD替换为稳定期特异性的RpoS,来调节转录装置。抗σ因子Rsd参与σ因子的有效替换,未使用的RpoD以Rsd-RpoD复合物的形式沉默储存。另一方面,功能性70S核糖体通过两种调节因子,即核糖体调节因子(RMF)和休眠促进因子(HPF),转化为无活性的100S二聚体。在这篇综述文章中,我们概述了我们如何发现这些因子以及我们对这些因子使转录装置和翻译机器沉默的分子机制的了解。此外,我们提供了我们最近对参与调控相关基因的转录因子进行启动子特异性转录因子(PS-TF)筛选的结果。结果共同表明Rsd和RMF对转录装置和翻译机器同时休眠的协调调控。